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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

36144 results found.

  1. GRB 051221: Swift/UVOT upper limits
  2. GRB 051221: Possible nearby cluster
  3. GRB 051221: No variability in Gemini data
  4. GRB 051221: Correction to GCN #4368
  5. GRB 051221: Gemini observations
  6. GRB 051221: Improved astrometry of the IR counterpart
  7. GRB051221: K-band source
  8. GRB 051221: XRT position
  9. GRB 051221: Refined analysis of the Swift-BAT short hard burst
  10. GRB 051221: IR Observations at GRB+1hr
  11. GRB 051221: Swift detection of a bright short burst
  12. Swift-BAT discovery of hard x-ray transient SWIFT J1626.6-5156
  13. Refined analysis of the Swift-BAT detection of the RS CVn star II Peg
  14. GRB 051211B: optical afterglow
  15. Swift detection of an RS CVn flare star
  16. GRB051211A: possible optical candidate
  17. Swift Trigger 172767 is not a GRB
  18. GRB 051215: near-infrared observations
  19. GRB051215 - SDSS pre-burst observations
  20. GRB 051215: Swift detection of a possible burst
  21. GRB 051215: A short GRB in a cluster?
  22. GRB051105: optical observations
  23. GRB 051213: Swift-BAT refined analysis
  24. GRB 051211B, optical observation
  25. GRB 051213: Swift-BAT detection of a burst
  26. GRB 051211a: RTT150 optical observations
  27. GRB051211B, RBO optical observations
  28. GRB 051211A: Swift/UVOT upper limits
  29. GRB 051211B: Swift/UVOT upper limits - correction
  30. GRB 051211B: Swift/UVOT upper limits
  31. GRB 051211A,optical observation
  32. GRB 051211B: Swift XRT confirmation of the afterglow
  33. GRB051211B: Liverpool Telescope observation
  34. GRB 051211b: RTT150 optical observations
  35. GRB 051211A and GRB051211B: BOOTES simultaneous observations
  36. GRB 051211B: Swift XRT Observations
  37. GRB 051210: Swift/UVOT upper limits
  38. GRB 051210: Magellan Imaging
  39. GRB 051211: TAROT optical limits
  40. GRB 051211B: a possible optical detection by TAROT
  41. GRB 051211B: a long GRB detected by INTEGRAL
  42. GRB 051211: Swift XRT upper limit
  43. GRB 051211:IAC80 optical observations
  44. HETE SXC localization of GRB 051211 (=H3979)
  45. GRB 051210: Optical imaging from Las Campanas
  46. GRB 051210: SALT detection limit
  47. GRB 051210: BAT further refined analysis of the short burst
  48. GRB 051210: Swift XRT refined analysis
  49. GRB 051210: FRAM early limit
  50. GRB 051210: Swift-BAT refined analysis of a short burst
  51. GRB 051210: A short GRB in a cluster?
  52. GRB 051210: Swift detection of a burst
  53. IPN observations of SGR1806-20
  54. An extraordinary long burst on December 3 from SGR1806-20
  55. IBAS Alert 2706 : not a real GRB
  56. GRB051117B: optical observation
  57. GRB051111: optical observaion
  58. Swift-BAT trigger 165579 is not a GRB
  59. GRB 051127: Swift-BAT detection of a possible burst
  60. GRB051117b: No Swift/UVOT Detection
  61. GRB 051117A: Swift/UVOT Detection of an Afterglow: Correction
  62. GRB 051117A: Swift/UVOT Detection of an Afterglow
  63. GRB051111: Suzaku WAM observation of the prompt emission
  64. GRB051008: Suzaku WAM observation of the prompt emission
  65. GRB 051109B: GAO 150cm telescope Optical limit
  66. GRB 051109A : GAO 150cm telescope Rc-band detection
  67. GRB 051021 Optical Observations
  68. GRB 051117B: MARGE Optical Limits
  69. GRB 051117A and B: Radio Observations
  70. GRB 051117B: R and I observations of possible host galaxy
  71. GRB 051117b: NIR observations
  72. GRB 051117A: Refined analysis of the Swift-BAT burst
  73. GRB 051117B: Refined analysis of the Swift-BAT burst
  74. GRB 051117B,optical observation
  75. GRB 051117B: Lulin R and I band observation
  76. GRB 051117B: Optical observations
  77. GRB 051117B: ROTSE-III Optical Limits
  78. GRB 051117B: Swift detection of a burst
  79. GRB 051117: Swift detection of a bright burst
  80. GRB 051028 Optical Observations
  81. GRB 051109B : Nainital upper limits
  82. GRB 051114: Radio Observations
  83. GRB 051114: Swift-BAT refined analysis
  84. GRB051109A optical observations
  85. GRB 051114: Swift-BAT detection of a short burst
  86. GRB 051111: Further spectroscopic analysis
  87. GRB 051111: Radio afterglow
  88. GRB 051113: Swift-BAT refined analysis
  89. GRB 051113: Swift-BAT detection of a burst
  90. GRB 051111: AEOS optical observations
  91. GRB051103: Radio Observations
  92. GRB 051109A Milagro GeV/TeV Observations
  93. GRB/SGR 050925: XMM-Newton ToO observation
  94. GRB051111: Swift/UVOT Observations
  95. GRB 051111A : R-band temporal decay index based on Lulin
  96. GRB 051111: Swift-BAT refined analysis
  97. GRB 051109A Optical Observations
  98. GRB 051111A : Lulin BVRI multi band afterglow observation
  99. GRB051111a: SARA Observations
  100. GRB 051111a: IR photometry

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